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When replacing stock bags snowballs into a Long Travel '04 Denali

13K views 66 replies 15 participants last post by  jglew82 
#1 · (Edited)
I guess just a brief intro. My name is Jason and this is my Wife's '04 Denali. We're the 2nd owners and we've owned it for roughly 4 years. It mainly gets the kids back and forth to school and the BMX track. I currently work at a Hot Rod Suspension company with access to some pretty cool tools, software & engineers.

The truck has mostly been neglected, other than receiving routine maintenance. It's been a great truck other than the common dash issue. When we bought it, it had some ugly a$$ 24" wheels on it. Those were ditched in favor of some 17" MB wheels with Nitto 285/70 Tires. I cranked the stock torsions roughly 2", made some jounce spacers and had it aligned.



I've added a Spectre Intake, Magnaflow muffler, and '05 Electric fans. My buddies at Gio's Performance tuned it for me as well.

Recently, the truck started swaying in turns and scaring the wife. It was getting so bad that She refused to drive it on the freeway. So I crawled underneath and glanced at the stock rear bags. Both bags had holes in them and the shocks appeared to be leaking. After a little searching I realized that stock replacement bags were more expensive than a good aftermarket set of shocks(Bilstein or maybe Fox's).

This is where things took a turn for the..........expensive. After measuring the stock shock pickup points I realized that I could fit a longer shock in place. Then the light bulb went on when looking at some aftermarket lift kits. It appeared that the stock 4-link would allow for a lot more droop than the stock shocks/bags could offer. So I put the back of the truck on jack stands and removed the stock shocks/bags. Inch by inch I let the rear axle down taking measurements and noting where any issues arose.

The stock shocks allowed for roughly 3" of droop from ride height.(keep in mind the bags weren't functioning so would likely be less with them working)

Here is what I found once the stock shocks were removed at one inch increments.
4" droop(shock centers 23.750") = ABS sensor on the frame needs to be turned 90 degrees
5" droop(shock centers 24.750" = Panhard bar is getting to a pretty extreme angle(need to go back and get a pic)
6" droop(shock centers 25.750") = The brake line bracket on top of the axle needs to be bent up roughly 15-20 degrees. The anti-sway bar contacts the diff cover.

6.25" droop(shock centers 26") = 18" Strap limits travel(*NOTE* The panhard bar has pulled the axle over 1" from center)

Here are a few more measurements with the 18" strap removed.
7" droop(shock centers 26.75") = The stock springs become unseated. Ride height sensors come undone, the lower link bar hits the positive stop on the axle bracket
8" droop(shock centers 27.875) = ABS sensor needs to be relocated and diff vent needs to be longer, need longer brake lines(20" or more)


While I was in there I went ahead and removed the springs and went the other direction. There is roughly 4" of compression from ride height(again bags not functioning). The shock centers were 17" with full weight sitting on the bump stop.

After a little research I found a shock that would be perfect in a 6" droop/4" compression scenario(from current ride height).

2" FOA 10" Coilovers are 16.5" closed and 26.5" open - Technically these are about the same price as factory replacement bags. I added in 18" straps as they are also the perfect length in this scenario.


Now, you may be thinking "Wait, those are coilovers". I plan on eventually swapping these to the front and replacing the rears with something even longer but smooth body.

Doing a little mock up. Just a hair over 10.25" of total travel using 9" of the available 10" shock travel.




18" strap mounted to the anti-sway bar bracket and lower shock hole, fits perfect.




I bent the brake line bracket up a little using the handle of the jack.


ABS Sensor turned 90 degrees.



There is some empty area above the spare tire mount for the reservoirs.


A typical reservoir mount was too tall so I made some low profile ones. Basically just some 1"x.125" bar bent into submission. I cut a slit in it to allow the clamp and then welded the hole shut.







I will likely mount the reservoirs directly to the shock body once these are replaced by smooth body shocks.


This is why a typical roll cage type reservoir mount is too high. There is just barely enough room above the factory fuel tank fill line for the reservoir line. Anything taller than a tight up against the floor mount will hit the lines.


The driver's side reservoir fits in place with no issues. The reservoir fits right in between the body and the front of the shock mount.


The Passenger side needs some slight trimming of the body and inner panel to clear the reservoir line. Because of the rear A/C lines the reservoir has to be installed behind the shock mount and then the line needs to be lifted over to the front of the shock mount.






Unfortunately, the FOA provided misalignment spacers are for 1/2" bolts so I ditched them and made my own for the stock 14mm bolts. The shock needs to be offset .25" in the upper mount(to the outside) so the shock body doesn't hit the shock mount.

The anti-sway bar link modification was fairly easy. I just cut the stock links in half and threaded them 1/2"-20 L/H & R/H and then just made a corresponding L/H-R/H sleeve. I'm sure the CJ links would be sufficient too but I wanted to have some adjustment for future height changes.




This has made an incredible improvement in performance. I look forward to addressing the front suspension to even up the score. The back handles so damn good now that the front is terrible in comparison.
 
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#37 ·
So the company I work for recently did some suspension work for a SEMA project for Toyo. I used that connection to get some new kicks. I'm still trying to work on American Racing Wheels which we also have a hook up on. I like the wheels currently on the truck but I need a set with less backspace.

305/70/17 Open Country A/T's





A little teaser of what's to come for the front. We use Chromoly material to build spindle pins for our front ends. I'll be using this material for some custom uniball mounts.

 
#40 ·
Wheels are the only thing I don't like about this build.
HAHA! I am 100% certain that the wife and I will not see eye to eye on wheel choice. When we bought these wheels I kept telling her that dark wheels will not look right on her dark truck. She fought me tooth and nail and eventually caved. After they were installed she instantly realized that she liked the machined look. We will likely stick with that theme on the next go round. I'd like to change the color of the beadlock though, if we end up with beadlocks. American Racing also owns KMC & ATX Wheels so I am looking at the....

XD222


& AX757





Which vehicle were you guys working on for Toyo? Just curious.
It was built by Demented Customs using our chassis/suspension.

 
#41 ·
Been busy with work the last few weeks so I haven't made much if/any progress. After working LS Fest West this past weekend and shooting some of the #DirtAlliance jump sessions I am beyond motivated to get this truck project going again.

Michael Cox's killer Bronco


Kibbetech's new truck


Darren Parsons from Dirt Alliance


Chris Isenhouer's F100
 
#43 ·
Feeling confident with the front bumper build I tackled the rear as well. Design wise was up to my wife even though I ended up without the step she asked for. Possibly will add it later.

I reused the factory brackets, just had to cut some holes and trim them back.

You can see the pilot hole for the hole saw.





A little mock up before bending the ends.







The front is still stock width so it looks silly with the McNeil fenders.



I added a couple bars to the front. The middle one being the most obvious. I also added one to the control arm crossmember and a short one that ties the center bar to the middle crossmember.

 
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#44 ·
thats different.
 
#45 ·
Are you going to add plates to the bumpers or just leave them open? They'd look a lot cleaner with something covering up the undercarriage imo
 
#46 ·
Oh yeah, absolutely! My brother has a 4'x4' sheet of .180w 6061 sitting around. I have access to a brake also so I will try to crease the center to match the center bar angle/bend. I also have dealings with Speedway so I will likely order a sheet of .125w plastic. I'll use this for the valence on either side of the skid plate. I am hoping they can bring it with them to the Street Rod Nationals in Louisville next month so I can save on shipping. http://www.speedwaymotors.com/Colored-Plastic-Rolls-10-Ft,1557.html
 
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#48 ·
With a little persuasion I convinced the wife that the Denali body moldings had to go. I figured removing the double sided tape was going to be the biggest issue. I did a little research and found that 3M makes what is called "Stripe Off Wheel". I removed a couple body pieces last night and messed around with the wheel. Holy crap that thing works. Albeit a little messy. I sprayed the dirty area down with water and wiped it clean. Then used a cordless drill at its slowest setting. It leaves a bit of a residue that is easily wiped off with a damp cloth. Afterwards I used a cleaner wax.



 
#51 ·
I decided to stick with stock length rear control arms for simplicity sake. The bars clear everywhere and thru full travel except when the anti-roll bar is disconnected and the suspension is fully articulated. The upper bar hits the frame slightly. The Johnny Joints are narrower than the mount opening so I had to shim them. I am fairly certain that I can just offset the bars/shims to gain the clearance needed. I ran out of daylight last night so I ended up just installing the stock upper bars again.







 
#52 ·
I know it's been forever since I've updated the thread. Life gets in the way. Meanwhile the Wife is driving around with stock front suspension and fiberglass fenders. Luckily, she doesn't care. Anyways, finally got the skid plate cut, bent and mounted.







Summer is coming up and I almost have the Lexus driveable again so the time to take the Denali apart to build the front end is approaching fast.
 
#55 ·
Not yet. In order to do this I need the truck to be down for quite some time. My back up vehicle is currently broke so we're in a holding pattern. I have a buddy with virtually the same vehicle that is willing to let me tear apart and use it for testing. I may go that route if I can't get the back up vehicle back together soon.

The wife's been driving it as is for quite some time now. Luckily, she's patient of the process.
 
#59 · (Edited)
874627


874628


We finally mounted some tires on the KMC Machette single beadlock wheels. The truck fills out the front fenders a lot better with these. 17x9 (I believe 0 offset)

Once again this project just keeps getting put on the back burner. Well, unfortunately, this time it's fate is uncertain. Since I last posted we have broken a driver side axle, broken another driver side hub, and most recently broken a passenger side hub. Each time this **** happens, I basically replace everything up front. This hub that just broke had maybe 1000 miles on it. This time we were lucky it was only at 20 or so mph. It ripped the caliper off the knuckle, broke the spindle and the wheel landed under the truck. The Wife did a great job of keeping her composure and got the truck off the side of the road with the wheel/tire as a crutch.


Note the tire wear in roughly 1000 miles
874629


Needless to say, something is clearly not happy with the front end right now. I gave up and just ordered a 4" lift for it hoping to correct CV angles(which is where I believe the problem lies). This was after extensive searching for a 1500 diff drop. Quite honestly, reading the internets for such products is quite interesting. Comment after comment about how the upper ball joints fail and the CV angle is fine after blah blah blah amount miles. Ball joints have never been a problem for me, just these damn axles and hubs. To add to my confusion there are diff drop kits for 2500's all over the place.

I still have the NNBS axles I bought years ago sitting in a box in the garage. Again, with the hopes of making custom arms roughly 2" wider. The 4" lift currently on order is not where I wanted this truck to be but I am backed into a corner. This is my Wife's daily driver and she loves the truck but I can't in good conscious let her drive it this way anymore. With my back up car also not drivable this has left us with one vehicle.

During this time (covid) parts availability has been an issue so the lift kit delivery date just keeps getting pushed back. In the meantime we looked and found an '02 2500 Suburban 6.0 in good mechanical condition, with great paint but the interior was thrashed. So we found a couple donor vehicles and made it super nice inside as well.

With the pressure off my shoulders now I can focus on the Yukon. I think now the Yukon will go to my Son (currently only 13 years old). Call it a project I guess but he loves the Yukon also but it damn well better be safe.

874630


The Suburban is now going to open up a whole new can of worms. The Wife is already looking at a cat eye conversion for it. I'm just over here trying to figure out how to get 15" of travel out of it. For those wondering, this truck is 2wd.

874631
 
#60 ·
Wouldn't be here posting without more drama. The Suburban was stolen from that exact spot out of our driveway at 7PM 2 weeks ago. I had made some progress on the Yukon the last few months. Given that the Suburban had taken over the daily duties the pressure to get it done was minimal. Now that the Suburban is gone I am back full time on the Yukon.

So here are some updates.

I received the Rough Country 4" lift (you know, the one they say doesn't work on a Denali). After first round of mock up with the NNBS axles I realized I needed to move the wheelbase. The drive axle was actually angled back going to the hub. Plus, I was sick of the rubbing at the back side of the fender well. So I promptly cut up the brand new RC crossmembers and moved the lower mounts forward 1.25".





Long story but the Cognito Uniball mounts weren't seating deep enough for my liking. While retapering one of the knuckles I messed up the angle. I contemplated replacing that one knuckle and then just said "eff it" and cut the upper ball joint mount off. Certainly not the best option having to weld cast. I captured as much area as possible, properly heat cycled them and also put a thru bolt to hold it all together(just in case).



2nd round of mock up proved to be interesting. I found all kinds of limitations. I had to cut off the factory UCA droop stop in order to clear the tie rod. Now, I had already cut part of it off with the old set-up but now it had to be completely removed. The sway bar is also going to be a restriction within about 3" of full compression. There might be a work around but for now I just lifted it up and out of the way. The lower ball joint is now the full droop restriction. The upper shock mount had to go. I also had to make new lower shock mounts that capture the stock bolt hole but move the new mount out further and lower. This was so that the 10" FOA Coilovers would fit properly. The NNBS axles are damn near perfect for the current situation. At full droop now the axle angle is roughly the same as it was before at ride height. So the bind it had before should be eliminated. Using 9" of shock travel (13.5-14" wheel travel) the CV's move freely everywhere. This is where it will be strapped and bumped, leaving .5" of shock travel at either end of the spectrum.

I sent the fenders and hood out to get painted. I also remounted the skid plate farther down in order to capture the new crossmember.

(roughly 2.5" of clearance between the tire and inner structure with a 33" tire) The plan was to run 35's eventually.



 

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#63 ·
The LAPD recovered the Suburban. Long story short, we were only allowed 20 minutes to inspect it on site so we decided to bring it home. Upon further inspection I don't think we're going to buy it back. The interior is just destroyed. Plus they covered it in fuel and left a ton of trash in the back. The harness was cut back all the way to the fuse boxes inside. My Wife can't even look at it without seeing red. Unfortunately, it is sitting right outside her kitchen window while we wait for AAA to pick it up.




I spent the last few days working on fabbing the passenger side UCA for the Yukon. This was a ton of trial and error. There isn't any room to spare for the coilover. I also had to cut part of the UCA mount in order to clear the UCA at full compression. I ended up shortening the UCA by about .5" in order to get more negative camber and have a little more caster adjustment. The material is .188w Chro-Moly. My next hurdle is going to be working out tie rods and fixing bump steer.



 
#64 ·
Almost a month later and the insurance company still hasn't picked up the Suburban. We couldn't wait any longer to replace it so we pulled the trigger on a '08 Denali XL. The price was right in spite of the ugly wheels and dreadful paint scheme. (Luckily my brother is a painter).




It has a few cosmetic issues on the front fenders and the driver side mirror is broke. Simple fixes but the previous owner had taken very good care of her.

It took me a few days do to our first mod. I made some 1" aluminum lower shock spacers at work. Then we yanked the tires off of the other Yukon's current wheels and installed them on the wheels we had on the Yukon previously. The scrub radius is a little more aggressive so I went ahead and modified the inner fenders and running boards to clear.



I took 2" off the running board.

 
#65 ·
What a tease this was. My neighbor has a set of 37" General Grabber's for his Toyota crawler. He let me borrow them for mock up on Bakon and damn did it look good. The reason it's a tease is because I already have a set of 305/70r17's waiting to go on the truck. Maybe some time in the future I will regear it and throw some of these on there.

I am glad I moved the wheelbase forward as far as I did because they actually cleared the rear part of the inner fender.

Note This is fully compressed





 
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